An Investigation of the Effects of Boundary Avoidance on Pilot Tracking

Pilot-Involved Oscillations (PIOs) remain a significant issue in the design, testing and operations of aerospace vehicles. Traditional methods for predicting, describing, and analyzing these events have provided the community with improved methods for minimizing the occurrences of PIOs. However, these events continue to occur over a wide range of aerospace vehicle types and over a wide range of pilot acumen. The introduction of boundary avoidance tracking (BAT) by Mr. William Gray in 2004 added a missing piece to the PIO puzzle. This theory presented that PIOs may result from increasing pilot gain resulting not from maintaining a specified condition, but avoiding imposed limits or boundaries on a specified task. The initial modeling and simulation conducted by Mr. Gray has provided the community with a starting point for applying this theory to the analysis of PIO events. This thesis characterizes BAT in the dynamic flight environment. Through the analysis of repeated BAT events in a T-38C aircraft, initial characteristic parameters for BAT have been identified and developed. The key BAT parameters were found to be independent of pilot and exhibited some dependence on aircraft load factor. Overall, BAT was successfully demonstrated and characterized during this research and the results will provide the community with a better understanding of the role BAT plays in PIO prediction and analysis